1. Field of the Invention
The present invention relates generally to the covering of solid, dry materials with a coating applied as a liquid. More specifically, the present invention relates to the coating of sheet construction materials (e.g., fiberglass insulation batts, gypsum wallboard, plywood and chipboard sheets, etc.) with a relatively thin coating of a heat reflective material known by the trade name Super Therm® to improve the heat resistance and insulating capabilities of such materials in building construction.
2. Description of the Related Art
Ever increasing energy costs have resulted in greater emphasis in energy efficient buildings and other structures over the years. Homes and other structures constructed much before the midpoint of the twentieth century were seldom provided with any significant insulation. At that time, the cost of the insulation material in comparison to energy costs, generally resulted in payback periods measured in decades. However, the rapid rise of energy costs of various types, i.e. electricity, natural gas, etc., have resulted in much greater interest in providing energy efficient structures than in past decades.
In many areas, homes and other structures are required to be constructed to meet certain minimum standards of energy efficiency. This generally results in at least three inch thick fiberglass insulation in exterior walls and at least six inches of ceiling insulation, if not more. Greater insulation capability is generally limited by the wall and ceiling thickness of the structure, as it is impossible to provide greater insulation effectiveness without substantially increasing the thickness of the insulation, when using loose fill and non-woven fibrous materials for insulation.
This is because such materials do not reflect heat, but rather serve to trap air in the insulating blanket. It is the trapped air, and not the material of which the insulation blanket itself is formed, which provides the insulation properties of the material. Such an insulating layer of air requires relatively great thickness, i.e. on the order of at least a few inches, in order to be effective. The primary task of the insulation material is to prevent circulation of the air within the material, and thus convection of heat from one side of the insulating space to the other.
The present inventor has developed a product which is sold under the trade name Super Therm®, which serves as a temperature barrier by means of a different principle. Super Therm® essentially comprises a waterborne, acrylic urethane resin based, ceramic filled material which may be applied as a relatively thin coating to reflect heat, rather than primarily serving as a dead air space as in conventional insulation. Super Therm® includes ceramic particles of specifically graduated sizes, with the different particle sizes migrating to different depths in the liquid coating before curing and serving to reflect electromagnetic energy of different wavelengths in the short wave, long wave, and infrared bands. Super Therm® is also highly thermally non-conductive when cured.
As such, Super Therm® is conventionally applied to relatively thin surfaces, e.g. sheet metal, asphalt, and fiberglass roof panels and the like, etc., where it is impractical or impossible to apply thick layers of fiberglass or other insulation material. Super Therm® is particularly well suited for application to the exterior surfaces of various structures, e.g. building and vehicle roofs, etc., although it can also be applied to interior surfaces as well, where it serves to reflect heat back through the panel to which it is applied.
As Super Therm® is typically applied to the exterior surfaces of relatively thin, planar structures such as roof sheathing, oftentimes no additional insulation batts or blankets are installed in such structures. Indeed, it has been found that the equivalent R value (thermal resistance) of a single coat of Super Therm® is R-19 equivalence, or about that of a fiberglass batt having a thickness of six inches. Accordingly, the application of one or two coats of Super Therm® having a thickness of only on the order of eight to sixteen mils is often accomplished in order to preclude the need to install thicker insulation material within the walls and ceilings of a structure.
The application of Super Therm® to the exterior or interior surfaces of a structure which is also conventionally insulated with relatively thick fiberglass batts, polystyrene foam material, or other thick, air entrapping material, results in even better insulation of the structure than if only one of the materials (either Super Therm® or air entrapping material) is used alone. As a result, Super Therm® has been applied to the exterior walls and roofs of many structures which are already insulated with conventional fiberglass batts or similar air entrapping insulation materials.
Yet, to the knowledge of the present inventor, Super Therm® has never been applied directly to such air entrapping insulation materials (e.g., fiberglass batts, etc.) or to panels of other building materials, except in testing by the present inventor. Such application would serve to increase the effective insulating values of the building materials, without need to apply a separate coating of Super Therm® to the exterior or interior surfaces of the structure, or to install additional thicknesses of air entrapping insulation material. There are good reasons why such application of Super Therm® to existing insulation and other building panels in the field, are not practicable. As with any liquid application, particularly when sprayed, there is a problem with overspray when applying the liquid to relatively small panels. Moreover, the additional labor required to coat such panels with Super Therm® or any other liquid product is not economically efficient in the field, when considering the typical hourly labor rates for the skilled labor involved in building construction.
As a result, the present inventor has developed processes and methods for coating such construction materials and panels with Super Therm® at the time of manufacture. This provides a number of heretofore unrecognized benefits: (1) The coating of the kraft paper backing side of fiberglass (or similar) insulation, results in the kraft paper providing the equivalent of thermal insulation (actually, primarily thermal reflection) in addition to the air entrapment of the insulation batt itself. Thus, such material when treated with Super Therm® essentially becomes two insulation components in a single sheet or batt of material. This is also true when Super Therm® is applied to the paper backing of a sheet of gypsum wallboard or to polystyrene or other plastic foam insulation board. A coating of Super Therm® to other building panels, e.g. plywood and chipboard panels, etc., results in those panels having insulation as well as structural properties. (2) The complete coating or encapsulation of a fiberglass batt with Super Therm® seals the fiberglass strands and prevents the escape of minute fiberglass particles from the batt. This eliminates the irritation commonly experienced by workers handling such materials as the minute glass particles imbed themselves in the skin and are inhaled. While such particles may hot be carcinogenic, they are definitely irritants, and the application of Super Therm® to such material at the point of manufacture eliminates this problem to workers in the field. (3) The application of Super Therm® at the manufacturing site results in such treated insulation panels having greater insulation efficiency. Thus, such treated panels may be only about half as thick as untreated panels, to provide the same insulating effect. This allows e.g. three inch thick batts to be used, where six inch thick batts would otherwise be required. In other words, twice as many Super Therm® coated batts providing a given insulation rating, may be contained and shipped in a given volume as compared to conventional, uncoated batts. (4) The elimination of overspray and similar problems in the field has been noted above. (5) The elimination of the labor costs of coating various materials with Super Therm® in the field, has also been noted further above. This also relates to the advantage of the economy of scale which may be achieved when coating various building materials with Super Therm® at the manufacturing site. (6) The addition of a coating of Super Therm® to a substrate sheet also improves the flame resistance, sound dampening, and mold and mildew resistance of the resulting composite material. Super Therm® has been tested and found to have zero flame spread, according to ASTM E-84-89 UL 723 test. Silver citrate is a Super Therm® additive which prevents organic growth (mold, mildew, etc.). Further tests have shown that a ten mil thick (dry) coating of Super Therm® can result in a reduction in sound transmittal through the Super Therm® and substrate composite, of 68%.
The present inventor is unaware of any process or method for coating or encapsulating sheet materials, and especially insulating materials, with Super Therm® or other thermally reflective liquid coating material, particularly at the point of manufacture before being shipped to the field for installation. A discussion of the related art of which the present inventor is aware, and its differences and distinctions from the present inventive method, is described below.
U.S. Pat. No. 5,085,897 issued on Feb. 4, 1992 to John S. Luckanuck, titled “Fire Retardant Insulation Spray Coating Method,” describes the formulation of a coating for structural steel members to insulate them in the event of a building fire, in order to prevent their collapse. The coating material is applied to a thickness of at least two inches and intumesces upon the application of extreme heat to provide a thick, air encapsulating blanket about the structure to which it has been applied. Such a thick coating is impracticable on relatively thin sheet construction materials such as plywood, gypsum wallboard, etc. While such a thick coating might be acceptable on thinner batts of fiberglass or similar insulation material, the thickness of the Luckanuck coating would preclude any flexibility for the batt, preventing it from being rolled for storage and transport or flexed into position during installation. Moreover, the Luckanuck coating cannot be applied at the manufacturing site for such steel support structures, as it would have to be removed from any connecting joints during the assembly of the structure, and then reapplied to any exposed areas of the structure after assembly. The very thin coating of the present material does not produce such problems, and may be efficiently applied at the building material manufacturing site.
U.S. Pat. No. 5,695,812 issued on Dec. 9, 1997 to Joseph E. Pritchett, titled “Method For Abating Bio-Hazardous Materials Found In Coatings,” describes the application of a coating material having the trade name of Rust Grip® to surfaces having asbestos and/or lead paints thereon. According to the '812 U.S. patent, Rust Grip® is a diphenyl methane diisocyanate based polyurethane containing proprietary additives and other metallics. The Rust Grip® percolates into any porosity in the underlying material, and bonds with the material to encapsulate and seal the material. The method of the '812 U.S. patent to the present inventor, teaches away from the method of the present invention in at least two respects: (1) The Rust Grip® coating does not provide any appreciable thermal barrier for the underlying material to which it is applied, as it has no ceramic or other particles which provide any thermally reflective or thermally non-conductive properties, and (2) there is no motivation to apply the Rust Grip material to new, clean panels of construction material at the time of their manufacture, when they are free of contaminants. The only appropriate venue for the application of the method of the '812 U.S. patent is in the field, where deteriorating asbestos insulation and flaking lead paint would be found. In contrast, the present method is directed to application at the point of manufacture of the underlying substrate material, to achieve the accompanying efficiencies of scale and control of application of the coating in such an environment.
U.S. Pat. No. 5,885,654 issued on Mar. 23, 1999 to Yoshio Hagiwara et al., titled “Polysilazane-Based Coating Solution For Interlayer Insulation,” describes the composition of an electrically insulating material (not thermally insulating or thermally reflective, as in the coating applied in the method of the present invention). The Hagiwara et al. coating uses a dialkyl ether as a solvent, rather than being water soluble as in the Super Therm® material used in the coating method of the present invention. Moreover, the Hagiwara et al. coating requires baking at extremely high heat to provide the desired electrical insulating property, and is particularly directed to application between electrically conductive films or the like, rather than being applied to the outer surface of a structural or insulating building panel, as in the present invention.
U.S. Pat. No. 5,985,433 issued on Nov. 16, 1999 to Daniel B. Leiser et al., titled “High Temperature Resistant Organopolysiloxane Coating For Protecting And Repairing Rigid Thermal Insulation,” describes a liquid material formulated for the repair of damage to thermally protective tiles and the like as applied to leading surfaces of reentry vehicles such as the STS (“Space Shuttle”). The Leiser et al. repair substance is not so much a heat reflective material, as it is a heat resistant material capable of withstanding extremely high temperatures and aerodynamic friction. As the Leiser et al. material is particularly adapted for the repair of damaged protective tiles, it clearly is intended for application in the field rather than at the manufacturing site, as in the present inventive method.
U.S. Pat. No. 6,251,971 issued on Jun. 26, 2001 to Chaofeng Chen et al., titled “Thermal Insulation Coating For Pipes,” describes an insulation material comprising microballoons in a water based epoxy material. Conventional hydraulic cement is mixed with the liquid immediately before application, to absorb the water for curing. The resulting product is quite brittle, as would be expected in a material containing a significant amount of concrete. This precludes the installation of such a coating to structural panels at their point of manufacture, as the coating would chip or flake off due to flexure of the panels during shipping and handling. The Super Therm® material used in the coating method of the present invention is relatively flexible and will not chip or flake off when the panel is flexed or folded.
U.S. Pat. No. 6,274,239 issued on Aug. 14, 2001 to Franco Peruzzotti et al., titled “Insulation Coating For Electric Cable Containing Polyolefin And Polymer With Ester And Epoxy Groups,” describes a composition having greater water resistance than other insulating coatings for electrical wiring. While the Peruzzotti et al. coating may be effective in providing a durable and water resistant, electrically insulating coating for wiring, Peruzzotti et al. make no disclosure of any thermally reflective and/or thermally non-conductive properties for their coating material. The Peruzzotti et al. coating would not be suitable for application to large, flat structural or insulation panels due to the relatively thick coating required for such resilient plastic materials, in any event.
U.S. Pat. No. 6,284,313 issued on Sep. 4, 2001 to Kent R. Matthews et al., titled “Coated Air Duct Insulation Sheets And The Like And The Method Of Coating Such Sheets,” describes a process involving multiple coats of a water soluble, latex base material to the otherwise uncoated surface of a fiberglass batt. The coats are apparently applied directly to the glass fibers on one side of the batt, rather than to any kraft paper backing on the batt. The Matthews et al. composition requires at least two heat treatments, with one treatment partially curing the first coat and the second heat treatment fully curing the two coats. No complete encapsulation of the glass fibers is disclosed by Matthews et al., and no thermally reflective or thermally non-conductive properties are described by Matthews et al. for their composition.
U.S. Pat. No. 6,338,366 issued on Jan. 15, 2002 to David R. Williams, titled “Pipe Insulation With A Jacket Measured In Fractions Of An Inch,” describes the forming of a thin sleeve having an open axial seam which may be spread to install the sleeve over a pipe. The sleeve is coated on either its inner or its outer surface, or both, with a heat reflective coating of from 30 to 250 mils. The coating is described as containing ceramic particles, but no specific range of particulate size and/or electromagnetically reflective wavelength is disclosed by Williams. In any event, Williams clearly installs his sleeves over existing runs of previously installed pipes. Otherwise, there would be no need to provide split sleeves for installation over the pipes. The present invention differs in that it teaches the application of a thermally reflective coating material directly upon at least one surface of a planar construction panel or blanket at the site of manufacture of the panel, rather than upon a sheet of material which is then applied over an existing installation, as in Williams.
U.S. Pat. No. 6,388,044 issued on May 14, 2002 to Yuji Yoshida et al., titled “Polyether Resin And Coating Solution For Forming Insulation Film,” describes a resin formulation for application to electronic components. The resin and coating of Yoshida et al. is electrically insulating, i.e. electrically non-conductive, but Yoshida et al. are silent regarding its thermal properties, other than to state that the composition is thermosetting.
U.S. Pat. No. 6,399,186 issued on Jun. 4, 2002 to Kent R. Matthews et al., titled “Coated Air Duct Insulation Sheets And The Like And The Method Of Coating Such Sheets,” is a division of the '313 U.S. patent to the same inventors, discussed further above. The same points of difference noted further above between the method and apparatus of the '313 U.S. patent and the present invention are seen to apply here as well.
International Patent Publication No. WO 94/25,644 published on Nov. 10, 1994 to Schuller International Inc., titled “Method And Apparatus For Preparing A Fibrous Batt,” describes an apparatus and method quite similar to that described in the '186 and '313 U.S. patents to Matthews et al., discussed further above. The Schuller International Inc. system also uses a thermosetting resin to coat fibrous batt material, unlike the air curing of the material used with the present inventive method. Moreover, Schuller International Inc. does not describe any form of thermal reflectivity or thermal non-conductivity for their resin, unlike the thermally reflective resin used with the present method.
Japanese Patent Publication No. 7-220,536 published on Aug. 18, 1995 to Hitachi Cable Ltd., titled “Electric Power Cable,” describes (according to the English abstract) an electrically insulating epoxy polymer for coating electrical cables therewith. No thermally reflective or thermally non-conducting properties are apparent in the English disclosure, nor is any disclosure apparent of the application of any coating to a planar construction panel, as provided by the present invention.
Finally, advertising materials provided by Superior Products, Inc., titled “International Energy Report” dated Apr. 1, 2001 and “Super Therm R20 Insulation Coating” (undated), illustrate and describe the properties and application of Super Therm® coating material to various substrates forming building structures in the field. Various substrates are described and/or shown, including concrete, tar, asphalt, and/or rubber coated roofs, shingles, various sheet metal surfaces, wood, and polyurethane foam. While fiberglass is mentioned, the material noted is not glass fiber material forming insulation batts, but thin cast or otherwise formed and cured, rigid fiberglass sheet material having no substantial thermal insulating properties. In fact, the only mention of such structural material in the Super Therm advertising materials is in combination with another Superior Products coating material known as Super Base(HS)®, and used as a base coat or primer. No disclosure is made of the application of Super Therm® directly to fiberglass insulation batts, either in the field or at the point of manufacture, nor is any disclosure made of the coating of any sheet building or structural materials with Super Therm® at the point of manufacture. Up to the development of the present inventive method, the entire objective of the use of Super Therm® has been for use in coating previously constructed structures, generally on their exterior surfaces, rather than coating or treating newly manufactured structural or insulating panels at the point of manufacture, as disclosed herein.
None of the above inventions and patents, taken either singly or in combination, is seen to describe the instant invention as claimed. Thus a method of applying a heat resistant coating to a substrate sheet solving the aforementioned problems is desired.